Jenelle Evans -- NOT MY HEROIN!

Jenelle Evans

NOT MY HEROIN!

4/25/2013 10:30 AM PDT BY TMZ STAFF

EXCLUSIVE

Former "Teen Mom" star Jenelle Evans DENIES she was in possession of heroin Tuesday at the time of her arrest.

A source close to Jenelle tells TMZ, Jenelle says the drugs recovered by police inside Jenelle's North Carolina home -- including 12 bindles of heroin and Percocet -- were not hers ... and she had no idea they were in the house.

Jenelle was also arrested for assault after allegedly attacking her husband with a piece of furniture -- but according to sources, Jenelle says it was self-defense during a domestic brawl. Her hubby was also arrested.